Grant Privett

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  • in reply to: Lunar Eclipse #579757
    Grant Privett
    Participant

    Yes, saw there was a lot of lightning over that way. Its all around Norwich now.

    Still no breaks here. Think I’m out of luck again.

    in reply to: Videos of the Warwick Meeting #579715
    Grant Privett
    Participant

    27 movies that fast? Heroic!

    in reply to: Photometry software issues #579683
    Grant Privett
    Participant

    Is that one of the USB 1.1 cameras?

    in reply to: BAA Council response to Exoplanet Section proposal #579653
    Grant Privett
    Participant

    I must admit, the exo-biology argument didnt work for me either. 

    Isnt detecting or monitoring an exo-planet pretty much the same as an eclipsing binary – albeit an extreme case?

    Would have thought it could live quite happily as a subsection of the VSS until it proves its longevity. Theres no reason progamme stars couldnt be chosen by the members or head of the subsection surely?

    in reply to: Updated proposal for an Exoplanet Section #579571
    Grant Privett
    Participant

    No one likes writing up meeting minutes quickly 🙂

    Actually, I have been thinking (try not to be shocked). The use of high precision photometry required for exo-planets, the high precision astrometry required for comets and the detailed spectroscopy of supernovae moves amateurs into situations where they are very much working at a level previously associated with professionals. So perhaps, whether or not the exo-planet section appears, the BAA needs to upgrade its pro-amateur collaboration efforts and perhaps focus a bit more effort on that to ensure those with the skills and inclination will be in demand and actively engaged.

    in reply to: Christchurch Weekend Meeting #579543
    Grant Privett
    Participant

    Thanks for the headsup.

    in reply to: Christchurch Weekend Meeting #579541
    Grant Privett
    Participant

    Hi Callum,

    Where will the DSS meeting be held next year?

    Grant

    in reply to: Liquid crystal shutters for meteor observing. #579528
    Grant Privett
    Participant

    Thanks for the info. Had assumed you had tried filtered and unfiltered driven pics to measure the actual extinction  – as manufacturers have been known to hype things and accidentally  forget to mention important caveats. Yeah, 37% is pretty painful though. Still worth thinking about though.

    in reply to: Liquid crystal shutters for meteor observing. #579520
    Grant Privett
    Participant

    Thats a really neat idea and I can see applications in other fields. How opaque do they become when energised? What sort of attenuation level could we hope for?

    I programmed a mechanical shutter to go off multiple time during a single Starlight H18 CCD exposure but, due to the time taken for the shutter to operate, its its not really plausible to work much above 5Hz and even then you are knackering the shutter mechanism, if you run it for long.

    Thanks for the report.

    in reply to: Bernard Lovell – work on meteors #579519
    Grant Privett
    Participant

    I think I heard Jodrell just got a large Lottery payment to invest in inspiring the next generation of scientists. Its good to see his legacy still playing a role in the country.

    in reply to: USB over Ethernet #579429
    Grant Privett
    Participant

    Just a quick update. As you may recall, I found that using a USB on my Dell E4310 meant the speed of the other USB socket was impacted. In fact, when a GPS dongle was being used to set system time, it meant the error could jump from 2-3 ms to 20ms.

    To try to overcome this, it was suggested I try an Expresscard based USB port. I bought a Startech dual USB2 port card, but had to return it as it wasnt recognised on Win7 – even after 30 minutes with one of their helpful online advisors. So I tried instead a CSL dual USB3 socket Expresscard for £10. After loading the drivers that was immediately recognised. It  works  fine  with all the USB kit I tried. So I connected the GPS dongle up to that, hung a Paramount MEII tracking a satellite (22Hz tracking speed updates) on one of the laptop USBs and a Starlight 694 taking very short exposures on the other. Result can be seen above. For long periods the error was 2-3ms with occasional wandering to 4ms. Really not bad at all – plugging into the main bus made a big difference. Well worth the small installation effort.

    So, if timing is crucial to you, get a standalone network enabled time source and set up your own NTP server. But if 2-3ms accuracy is good enough, £20 for a GPS dongle and a CSL card will do the business.

    in reply to: USB over Ethernet #579356
    Grant Privett
    Participant

    Thats interesting. As my previous problem had been using a USB sound sampler on a shared port, I thought I should check again.

    So, I was out last night using a USB GPS dongle and NMEATIME2 to set my system clock to <0.005s accuracy, controlling a telescope from TheSkyX  (which uses a  USB to Serial converter to talk to a Paramount)  and a Starlight camera via a USB socket.

    The laptop I used was a Dell E4310 (Intel i5 at 2.4GHz with 4GB memory) which only has 2 USB sockets.

    I noticed that when anything was sharing a socket with the dongle, the NMEATIME2 correction timings became erratic – it assumes GPS  fixes from the receiver are evenly spaced I think. So, when I connected the telescope or when sharing with the CCD my timing precision was potentially off as the attached image demonstrates (the sharp change in the trace is when I connected the telescope). Not surprising I suppose, but the timesharing aspect clearly does have some an effect on other bus users. I imagine the impact will depend upon the nature of whats sharing the port and what laptop manufacturer/model you choose.

    I will try again tonight if (wonder of wonders) we get two clear nights in a row using a Dell D630 which has 4 USB ports and post the results here. Alas, I only have Dell laptops and so cannot say how this pans out with other machines. 

    in reply to: Observatory Sheds in Spain? #579407
    Grant Privett
    Participant

    Do let us know what you find out. A commercial manufacturer of roll off roof sheds would be worth knowing.

    in reply to: USB over Ethernet #579371
    Grant Privett
    Participant

    Yes. That makes sense. Had wondered about getting an additional USB socket on an Express card. Hadnt thought of the docking station though (I do have one somewhere). Might get a spare docking station while they are still available – I have a feeling the later Dell models also have a connector, but its a different format – will worry about that when I upgrade (I’m a fan of kit thats oldish, so that when it breaks it is not an expensive event – good for the stress levels.).

    Will grab a card and let you know how it turns out.

    in reply to: Hyperstar Use. #579349
    Grant Privett
    Participant

    I recall him saying collimation was hard work and important if you were using a large sensor.

    in reply to: Ooops! #579308
    Grant Privett
    Participant

    Good to see those working at the department of HEM getting proper recognition.

    in reply to: USB over Ethernet #579285
    Grant Privett
    Participant

    Separate networks sounds a good idea. Sneaky 🙂

    in reply to: USB over Ethernet #579280
    Grant Privett
    Participant

    Glad to hear I havent got it completely wrong then. It is very reassuring to hear other people already do this.

    I made sure the Dell I am thinking of is W7 rather than XP on because XP doesnt get security upgrades anymore. 

    Now, if I can just get the garden sorted and the redecoration done and the skirting boards replaced and the paths laid and the…..

    This will be fun.

    in reply to: USB over Ethernet #579244
    Grant Privett
    Participant

    I did try a Dell D630 30ft away from the house in the garden, with a CCD attached and it seemed to work fine when accessed by Remote Desktop and a Wifi connection. It happily sat there taking 5s exposures for me and displaying them. I didnt even need to move my Hub from the other end of the house – I will probably add a repeater when I use it in anger (theres minor issue of putting a  pier in, adding the mount/scope and adding an observatory to be overcome yet) or add a couple of ethernet cables to the trunking carrying the mains out there. 

    I’m not sure why more people are not using Remote Desktop. What dumb error am I making? Security?  🙂

    in reply to: USB over Ethernet #579217
    Grant Privett
    Participant

    A key fob on the roll off roof is pretty cool 🙂

    Will indeed look out for well protected cables. We have foxes round here certainly – the footprints in the recent snow were really obvious. Other things too – though pheasants, deer and voles are not normally a problem for telescopes, but rather unwelcome in the nearby veg patch.

    I noticed several people mentioned the software they use to access the instruments in the observatory from indoors. Sounds like there are several good options out there – and some of them free to private non-commercial users. Its nice to have multiple good choices. I’m rather favouring using Dell D630 laptop outside as they have  4x real USB sockets and are rather cheaper than decent spec NUCs – t he NUC may come later (its compactness is attractive). Dell D630s are certainly not  the fastest machines in the world but good enough to run an autoguider and CCD at the same time.

Viewing 20 posts - 361 through 380 (of 470 total)